TOML Formatter

Paste messy TOML and get it tidied up: consistent spacing around the equals sign, a blank line before each table header, trailing whitespace stripped, and extra blank lines collapsed. It turns hand-edited config that's drifted out of shape — title="x" here, name = "y" there — into something clean and consistent.

TOML (Tom's Obvious, Minimal Language) is the config format behind Rust's Cargo.toml, Python's pyproject.toml, and a lot of other tooling. It's designed to be easy to read and write by hand, which means it's also easy to leave inconsistent: mixed spacing, no separation between sections, stray blank lines. This tool cleans that up without changing what the config means.

Click Format to run it, or Load sample to see it work on a typical config with tables, arrays, and inline values. It's a tidier, not a validator — see the notes for what it does and doesn't touch.

Formatting is line-based, which suits TOML because TOML ignores indentation entirely — nesting is expressed through [table] and [[array-of-tables]] headers, not whitespace. For each key/value line it finds the top-level equals sign (skipping any = that sits inside a quoted key), then rewrites the line as key = value with exactly one space on each side. It puts a single blank line before every table header, strips trailing whitespace, and collapses runs of three or more blank lines down to one.

Crucially, it tracks state so it doesn't corrupt multi-line constructs. When a value opens a multi-line array ([ that isn't closed on the same line) or a multi-line basic/literal string (""" or '''), the following lines are passed through untouched until the construct closes. That means an = sign inside a multi-line string won't be mistaken for a key/value separator, and a formatted array keeps your chosen layout.

It's a formatter, not a parser or validator — it won't flag TOML syntax errors, resolve dotted keys into nested tables, or reorder anything. Everything runs in your browser; nothing is uploaded.

A real TOML library (like Rust's toml crate or Python's tomllib) parses your config into a data structure and can re-serialize it in a canonical form — that's more thorough but also reorders and rewrites more aggressively, and it rejects invalid input outright. This tool takes a lighter touch: it tidies spacing and spacing between sections while leaving your structure and ordering exactly as written, which is what you usually want when cleaning up a file you'll keep editing by hand.

Use a full parser when you need validation or guaranteed-canonical output for a build pipeline. Use this for a quick visual cleanup of a config file before committing it. If you need to convert between formats, a JSON-to-YAML or dedicated converter is the right tool — this only formats TOML, it doesn't convert it.